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Hydroquinone is the LeBron James of skin care. The skin lightener is as controversial as it is effective. When incorporated into your complexion regimen properly, hydroquinone decreases the production of melanin by inhibiting tyrosinase, an enzyme needed for melanin production, to decrease the appearance of hyperpigmentation. Because of this, many people consider it to be a skin-bleaching ingredient. According to Miami-based board-certified dermatologist Roberta Del Campo, it should be considered a “color blender” instead.
Things can go wrong (namely, a rare, unwanted side effect called exogenous ochronosis, “which is a paradoxical darkening of the treated skin,” Louisiana-based board-certified dermatologist Mamina Turegano tells Allure) if you don’t meticulously follow the dos and don’ts of hydroquinone, though.
Plus, the ingredient has been banned in Europe since 2001 on account of studies finding evidence of carcinogenicity in rodents when hydroquinone was orally administered. The U.S. Food and Drug Administration (FDA) took this into account and still deemed hydroquinone safe for topical application because not enough clear evidence of the risk outweighing the benefits exists. Dermatologists also are still willing to prescribe it to their patients.
Needless to say, we felt compelled to ask board-certified dermatologists to walk us through exactly what you need to do with the melasma remedy for it to be a safe, beneficial part of your skin-care routine.
DO consult your dermatologist first
Before implementing hydroquinone into your lineup, ask your dermatologist if it’s truly right for your skin tone and complexion concerns. Although it is suitable for all skin types, Turegano is cautious when recommending the ingredient to those with dry and sensitive skin because of the irritation it can cause. She’s also wary of those with deeper skin tones incorporating hydroquinone into their skin-care routines because the risk of exogenous ochronosis is higher than those with fairer complexions. Hydro isn’t off the table in these cases, but caution and close monitoring is needed.
DON’T use hydroquinone for too long
A major key to hydroquinone is short-term use. You can slather it on twice daily for at least six weeks (and no more than six months). After one to three months, you should start to see your hyperpigmentation fade away. At the three-month mark, you should set it aside. “Once you have achieved your desired results, stop using hydroquinone daily and only use it if the hyperpigmentation reappears,” says Aegean Chan, a board-certified dermatologist based in Santa Barbara, California.
DO wear (and reapply) sunscreen daily
Although sun protection is a given no matter what you’re putting on your face, it’s an essential worth stressing. Layering on ample sunscreen and diligently protecting your skin from UV exposure yields the best results with hydroquinone, Chan says.
DON’T mix hydroquinone with these ingredients
Turegano and Chan both agree hydroquinone does not play well with benzoyl peroxide, hydrogen peroxide, or other peroxide products. Not only will pairing them cause irritation and dryness, but it can also temporarily stain your skin.